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UNITED STATES' i PATENT OFFICEy Y .IAMES T. IIAYDEN, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE CRANE COMPANY, OF SAME PLACE.

AIR-PUMP GOVERNOR.

SPECIFICATION forming part of Letters Patent No. 513,106, dated January 23, 1894. Applicationiled July 22,1893. Serial llo-481,196. (No model.)l

To all whom, it may concern.-

Beit known that l, JAMES T. HAYDEN, acitizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Air-Pump Governors, of which the following is a full, clear, and exact de-y to produce an air-pump governor which shallv be simple and durable in its construction and positive and reliable in its action, and which also shall not be liable to derangement of its.

operative parts. Furthermore to produce an air-pump governor which shall be so constructed that, in the remote contingency of disablement, certain parts of the governor can be readily removed so as to enable the compression-system to continue in operation without impediment by a disabled governor.

To the above purposes, my invention consists in certain peculiar and, novel features of construction and arrangement, as hereinafter described and claimed.

The more precise nature ot' my invention will be better understood when described with reference to the accompanying drawings, in which-- Figure lis a side elevation of an air-pu mp governor embodying my invention; the lower part of the casing being partly broken away to more clearly show the construction of the steam-valve and its seat. Fig. 2 is a transverse vertical section, of the air-pump governor, taken on the line 2-2 of Fig. 1.

In the said drawings l designates the shell or casing for the steam-valve of the governor, this shell or casing being preferably (although not necessarily) somewhat globular in form, and being formed at one side with an inletnipple 2 and at its opposite side with an outlet-nipple 3. These inlet and outlet nipplesy u are shown as externally screw-threaded, to receive thensual coupling nuts or glands, but they may be of any other desired form, as circumstances may suggest; the-inlet nipple 2 communicating with a source of steam supply and the outlet-nipple 3 communicating with the steam-chest of an air-pump.

Vithin the shell or casing lis formed a transverse diaphragm or partition 4 havinga central opening or valve-seat 5 and so placed that steam entering through the inlet-coupling 2 must pass through .the opening 01 valveseat 5 before it can pass to the outlet-coupling 3. The bottom of this casing or shelll is formed with a straight downward extending neck 6 the lower end of which is usually closed by a removable cap or plug 7; said cap being shown as screw-threaded into the lower end of the neck. As will appear from the ensuing description of the governor, this removablecap performs an important function in the governor, and I therefore desire it to be understoodthat the cap may either be screwed into the neck of the casing 1, or that it'may surround said neck, or that it mayin any suitable manner tightlybut removably close an opening in the bottom of the casing.

In one side of the casing l is formed a vertical passage or channel 8 the lower end of which communicates, by a short lateral port 9, with the interior of the casing'at a point below the diaphragm 4. The upper end of this vertical channel communicates, by a lateral passage or channel 10, and a short vertical port l1, both formed in the top ofthe casing, with the interior of the casing ata point above the diaphragm 4; the purposes of these channels S, and 10 and ports 9 and hereinafter fully explained.- Y

12 designates the steam valve whicli'isfof such form and dimensions as, at times, to closethe opening or valve seat 5 in the diaphragm 4; the lower margin of the opening 5 being.

dressed or beveled to form a tight seat for said valve. Frein the underside of this valve 12 depends a short stem 13 the lower end of which carries a piston 14 which is of greaterl Il Abeing IOC diameter than the steam-valve 12 and of such` form as to fit closely, but movably, in the neck 6 of the casing 1; the piston being preferably provided with a packing 14", as shown, to insure tightness. Moreover, the piston 14 is also formed with a leak passage or channel 15 extending vertically through its body and of comparatively slight diameter; the purpose of this leak-passage being also hereinafter fully explained. A spiral spring 16 is shown in dotted lines as located in the neck 6 and as resting upon the cap 7, this spring tending, by upward pressure against the under side of the piston 14, to raise the valve 12 into closed position.

The top of the casing 1 is formed with an internally screw-threaded opening 17 into which ts the externally screw-threaded lower end of a piston-casing 18; this casing 18 being preferably of tubular form, as Shown, and extending vertically upward from the top of the valve-casing 1. At one side this pistoncasing 18 is formed with an a-ir-outlet or vent opening 19, and at its upper end, said casing is formed with a piston-chamber 2O within which fits, movably, a piston 21; said piston being preferably provided with a packing 22. From the under side of the piston 2l extends downwardly a stem 23 which is vertically movable in a channel 24 leading vertically downward from the piston-chamber 2O and opening at its lower end into the transverse channel 10 of the valve-casing 1,in precise axial alignment with and above the short vertical channel 11 of said casing 1. The lower extremity of the stem 23 is tapered to form a needle-shaped piston-valve 25 which, when the piston 21 is depressed, iinds its seat in the upper end of the short vertical port 11, just referred to. A spiral spring 26 rests upon the bottom of the cylinder-casing 18 and surrounds an internal vertical boss 27, rising from the bottom of the casing (and having the channel 24 formed centrally through it); the spring 26 tending, by upward pressure against the under side of the piston 21, to raise said piston and thus to open its piston-.valve 25, for a purpose also to be hereinafter explained.

luto an internally screw-threaded opening 28, at the top or upper end of the piston-casing 18 is fitted the externally screw-threaded and open lower end of a gage-valve casing 29 which is formed with an internal diaphragm or partition 30 having a short vertical channel 31 extending therethrough. At a point above the diaphragm or partition 30 is an` air-inlet opening 32 formed laterally through one side of the gage-valve casing 29, and assuming externally the form of a nipple which is tobe suitably coupled either to the engineers air-valve (in the casing of rail-waytrain service) or to the train pipe, or to the main reservoir; or, in other situations, to any receptacle for compressed air.

Into the internally screw-threaded upper end 33 of the gage-valve casing 29 is fitted the externally screw-threaded lower end of a screw-threaded regulating-cap 35. At one side, near its lower end, the casing 34 is shown as formed with a small lateral outlet or vent opening 36, and the lower end of said casing is cupped or concaved to form a seat 37 for the gage-valve piston 38 which works in a chamber in the upper part of the casing 29. From the gage-valve piston 38 extends upwardly a guide-stem 39 the upper end of which enters a guide recess or socket 40 in the top of the regulating-cap 35, and which is surrounded by a spiral gage-spring 4l; said spring being interposed between the top of the cap 35 and the upper side of the piston 38.

From the under side of the gage-valve piston 38 depends the stem 42 of the gage-valve 43; this valve being of the needle type, formed by tapering the lower end of the stem, and finding its seat in the upper end of the short vertical channel 3l before referred to. The stem 42 is shown as having at its upper end a head 44 which enters a recess in the under side of the piston 38 and which is retainedin said recess by a plug 45 screwed into the nnder side of the piston; this construction being, however, of minor importance, although it has the advantage of rendering the gagevalve 43 detachable from its piston.

The operation of the above-described pumpgovernor is as follows--assuming the airpump to be in operation, and the air-pressure to be below the predetermined limit (say, seventy-live pounds to the square inch). Such being assumed as the initial working condition, the gage-spring 41 (which is also assumed to be set at say seventy-five pounds) will hold the gage-valve 43 down in its seat, closing the upper end of the channel 3l, as shown in Fig. 2, so as to prevent the passage of compressed air therethrough. The spring 26 will, in this event, also retain the piston 21 in elevated position, so as to hold the needle-valve 25 open or out of its seat, as also shown in Fig. 2; thus leaving the short vertical channel 1l open. With the valves 43 and 25 in the position just described the steam-valve 12 will also be open or unseated from the opening 5 in the partition 4 as shown in Fig. 2; the steam at such time flowing freely through the valve-casing 1 and to the pump, and this being the normal working condition of the governor, during the operation of the air-pump. A certain portion of the steam will, meantime flow through the leak-passage 15 of the steam-valve piston 14 and will fill the space below said piston, and will also fill the vertical channels 8 and lateral channels 9 and 10 and passing through the channel l1 will enter the space above the diaphragm or piston 4. As the air-pump continues to operate, it will gradually raise the air-pressure up to the predetermined limit (in this instance, say, seventy-five pounds) and thereupon the compressed air, pressing IOO IIS

upward beneath the piston 38, will raise said piston against its spring 41 (the vent 36 permitting the dead air above the piston to escape) and will open or unseat the gage-valve 43. The compressed air will then be free to flow through the channel 31, and acting upon the piston 21, will force said piston downward against its spring 26, seating the valve 25 in the upper end of the channel 11, and cutting oft steam from said channel, the vent-opening 19 permitting the escape of dead air from beneath the piston 21, during the descent of said piston. closed, the imprisoned steam in the chamber below the piston 14 and in the passages 8, 9, and 10, reinforced by the steam which continues to iiow through the leak-passage 15, quickly equalizes the steam pressure upon the upper side of said piston 14, and thereupon the steam-pressure beneath the steamvalve 12 (acting in conjunction with the spring 16) serves to seat the steam-valve 12 in the opening 5 of the partition 4; thus outting off steam from the air-pump and so stopping the action of said pump. When, by reason of application of the air-brakes, or from any other sufficient expenditure of the compressed air, the air-pressure again falls below the predetermined limit, the. gagespring 41 will close the gage-valve 43, and the spring 26 will open the piston-valve 25. The steam will now instantly enter the passage 11, and being exhausted through the outlet-nipple 3, to the pump, the superior steam-pressure upon the upper side of the piston 14 will depress said piston and open or unseat the piston-valve 12 so as to permit the steam to How through the valve casin g 1, from the inlet nipple 2 and through the outlet-nipple 3, and thus to again start the pump. The subsequent operations of the governor will be repetitions of those just described.

It is to be observed that by turning the screw-cap 35 in one or the opposite direction, the pressure of the gage-spring 41 upon the piston 38 of the gage-valve 43 can be increased or diminished, so as to correspondingly increase or decrease the limit of air-pressure necessary to raise-or open the gage-valve. It is also to be further, and particularly, observed that, in the event of any derangement of the steam-valve and its piston, such valve and piston can be readily removed bodily from the governor, after simply unscrewingY disablement of the governor thus in no Way disabling the entire air-system, as heretofore, especially vin air-brake systems of railway trains. Y

I would still further observe that, inasmuch as it is the steam-pressure which primarily raises and lowers the steam-valve piston 14,

When the needle-valve 25 is to seat and unseat the steam-valve, the spring 16 may be dispensed with, if desired. However, for the sake of certainty, it is usually preferable to use the spring 16 to assist the steam in raising the piston 14;v and if desired a similar spring 50 (shown in dotted lines in Fig. 2) may also be used to assist the steam in depressing the piston 14; the spring 50 being interposed between the upper side of the piston andthe under side of the partition 4 and surrounding the stem 13 of the steamvalve.

Having thus described my invention, what 1 claim as new therein, and desire to secure by Letters Patent, is-

1. An airpump governor, comprising a steam-valve casing having a transverse partition provided with a valve-opening and dividing the interior of the casing into a pistonl chamber below the partition and a steam-discharge chamber above said partition, asteamvalve having its seat in the lower side of the valve-opening, a piston connected rigidly with the valve and of greater diameter than said valve, and also provided with a leak channel, and a by-pass establishing communication between the piston-chamber and the dischargechamber, the piston being exposed both above and below to steam-pressure within the piston-chamber, substantially as set forth.

2. An airpump governor, comprising a steam-valve casing located at the lower end of the governor and having a removable cap for closingiits bottom, a removable steamvalve working in said valve-casing, and aircontrolled valve-mechanism wholly separate, both operatively and structurally, from the steam-valve, and located above the steamvalve casing and operating to vary the steampressure upon the steam-valve, substantially as set forth.

3. An air-pump governor, comprising a steam-valve casing located at the lower end` of the governor and having a steam-valve working in said valve-casing and carrying a piston of greater diameter than the steamvalve, steam-channels establishing steamcom m unication with the valve-chamber above and below the steam-valve and piston respectively, and air-controlled mechanism located above the steam-valve casing and operating to open and close the steam-channels, so as to vary the steam-pressure upon the steam-Valve and its piston, substantially as set forth.

4. An air-pump governor, comprising a steam-valve casing forming the lower end of the governor and also provided with a transverse partition having a valve-opening, steam inlet and outlet openings, andsteam passages establishing steam communication between the upper and lower parts of the valve-chamber a steam-valve workingl in said valvechamber and carrying a piston provided with a leak-channel and of greater diameter than the steam-valve, and air-controlled valvemechanism located above the steam -valve casing and operating to open and close the IOO IIO

steam-channels of Vsaid. Valve-casing so as to vary the steam-pressure upon the steam-valve and its piston, substantially as set forth.

5. An air-pump governor, comprising a steam-valve casing forming the lower end of the governor and provid ed with lateral steam channels establishing communication between the upper and lower parts of the steamvalve chamber, a steam-valve workin g in said valve-chamber and carrying a piston of greater diameter than the steam-valve, an air controlled piston working in a chamber located above the steam-Valve casing and carrying a valve for Opening and closing the steam-channels of the steam-valve casing, an air-controlled gage-valve piston working in a chamber located above the air-piston chamber and carrying a gage-valve for opening and closing a port leading to the chamber of said air-piston, and a gage-spring pressing upon the gagevalve, substantially as set forth.

6. `An air-pump governor, comprising a steam-valve casing forming the lower end of the governor and provided with lateral steamchannels establishing communication between the upper andlower parts of the steamvalve chamber, a spring-pressed steam-valve working in said valve-chamber and carrying a piston of greater diameter than the steamvalve, an air-controlled piston working in a chamber located above the steam-valve casing and carrying a valve for opening and closing the steam-channels of the steam-valve casing, an air-controlled gage-valve piston working in a chamber located above the air-piston chamber and carrying a gage-valve for opening and closing a port leading to the air-piston chamber, an air-inlet opening below said gage-piston and above the gage-valve port, a gage-spring located above the gage-valve piston and pressing thereon, and an adjustable screw-cap pressing upon said gage -spring, substantially as set forth.

JAMES T. HAYDEN.

Witnesses:

` TODD MASON,

V. HUGO. 

